Here is the full list of all 43 SpongeBob's Truth or Square achievements worth 1,000 gamerscore.
You watched all of the credits.
You completed the game.
You upgraded all of SpongeBob's furniture.
You found all of SpongeBob's Happiness Objects.
You found the Picnic Basket.
You found the Volcano Hot Sauce.
You unlocked all concept art.
You survived all 7 Task Tiki Combat Challenges.
You found the Karate Gloves.
You found Patrick sleeping in all levels.
You found Mr. Krabs' 1st Dollar.
You found Patrick's Alarm Clock.
You unlocked all of the available costumes.
You found the Open 24 Hours sign.
You collected 10,000 Happiness Nuggets.
You found the Krabby Patty.
You found Mermaidman & Barnacleboy's Ring Box.
You found Mermaidman's Utility Belt.
You found the Aquaphone.
A Co-op buddy, as Plankton, defeated 100 enemies.
A Co-op buddy, as Plankton, shook 50 enemies.
A Co-op buddy, as Plankton, made 100 Happiness Nuggets sad.
You collected 99 Lives.
You found the Bellybutton Lint Earmuffs.
You found Squidward's Paints.
You found the Toy Clarinet.
You broke 1000 Plankton Tikis.
You found Snellie's Pet Carrier.
You found the #1 Soda Drinkin' Hat.
You found the Golden Spatula.
You fed Patrick a kelp hot dog.
You found the Hot Dog.
You found the Heart-Shaped Acorn.
You found the Magic Conch Shell.
You broke 150 Squidward Stone Tikis.
You defeated 250 enemies with SpongeBob.
You completed a level without dying, without invincibility.
You found Sandy's Iced Tea Glass.
You found the Bubble Wand.
You found the Baby Jellyfish.
You found SpongeBob's Jellyfishing Net.
You defeated 30 enemies in a row while buff.
You made SpongeBob grow old.